This invention relates to new chemical compounds which are of value as antibacterial agents. More particularly it relates to certain new bis-esters of methanediol, in which one hydroxy group of the methanediol has been esterified with the carboxy group of a 6-(2-amino-2-[4-acyloxyphenyl]acetamido)penicillanic acid compound and the other hydroxy group has been esterified with the carboxy group of a beta-lactamase inhibitor. Said latter beta-lactamase inhibitor is one of the type which contains a beta-lactam ring as well as a carboxy group.
U.S. Pat. No. 4,244,951, Belgian Pat. No. 887,173 and published British patent application No. 2,044,255 disclose a variety of bis-esters of methanediol of the formula ##STR1## and the pharmaceutically-acceptable salts thereof, wherein R.sup.1 represents certain acyl groups and the radical W--C(.dbd.O)--O-- represents a radical of a betalactamase inhibitor, W--C(.dbd.O)--OH, which contains a beta-lactam ring as well as a carboxy group, said compounds of formula I being useful as antibacterial agents. In particular, R.sup.1 can represent a 2-amino-2-(4-hydroxyphenyl)acetyl group. However, it has now been found that compounds of the formula I, wherein the group R.sup.1 represents certain 2-amino-2-[4-acyloxyphenyl)acetyl groups, constitute a new genus of bis-esters of methanediol, having outstanding value in the treatment of bacterial infections in mammals. Additionally, compounds of formula I, in which R.sup.1 represents certain 2-(protected amino)-2-(4-acyloxyphenyl)acetyl groups, are useful as intermediates to the antibacterial agents of this invention.
The antibacterial agents of the present invention are efficiently absorbed from the gastrointestinal tract of mammals, and after absorption they are transformed into 6-(2-amino-2-[4-hydroxyphenyl]acetamido)penicillanic acid (amoxicillin) and a betalactamase inhibitor.
6-(2-Amino-2-[4-hydroxyphenyl]acetamido)penicillanic acid and 6-(2-amino-2-[4-acyloxyphenyl]acetamido)penicillanic acids are known; see further U.S. Pat. Nos. 2,985,648, 3,520,876 and 4,053,360. Penicillanic acid 1,1-dioxide is known from U.S. Pat. No. 4,234,579.